Prior to 49690f9, BlockFaces were mostly correct in their respective
MaterialData classes. However, a lot of things were not updated since
implementation and broke without being addressed.
This fixes any discrepancies with Block data.
If you use BlockFace in any way, to compensate the directionals being incorrect, you can still have backwards compatibility if you add in the handling in your plugin:
boolean legacyBlockFace = BlockFace.NORTH().getModX() == -1; (and then handle it accordingly)
If you didn't special case your directions to fix what's being fixed here... Hurray! Your plugin should now work.